The present invention relates to an air compressor.
To reduce carbon dioxide emissions, development of an electric vehicle using a fuel cell has been conducted. The fuel cell generates electric power through an electrochemical reaction between oxygen and hydrogen which are supplied to the cathode and the anode of the fuel cell, respectively. In such electric vehicle, an air compressor is used for compressing air and oxygen in the compressed air is supplied to the cathode of the fuel cell. There is generally a problem of noise occurring from the intake and discharge ports of the air compressor and, therefore, various compressors have been developed to reduce such noise.
For example, Japanese Unexamined Patent Application Publication No. 2003-285647 discloses an arrangement of an air compressor and its related components in a fuel cell vehicle for reduction of noise development around the compressor. In the publication, an air cleaner is connected through a rubber tube to the intake side of the compressor, and a chamber or plenum chamber forming therein a box shaped space is provided between the rubber tube and the intake side of the compressor in order to reduce the radiation noise from the rubber tube due to the intake pulsation noise generated at the intake side of the compressor. The plenum chamber is provided therein with a sound absorber. The plenum chamber functions to reduce the intake pulsation noise from the intake side of the compressor, resulting in a reduction of the radiation noise from the rubber tube which is difficult to be reduced because of low rigidity of the rubber tube.
The arrangement disclosed in the publication No. 2003-285647 in which the plenum chamber is connected to the intake side of the compressor requires a large space for installation of both of the compressor and the plenum chamber in a vehicle. Such large installation space affects the arrangement of many other components in a vehicle and hence is difficult to be provided. In addition, when the compressor and the plenum chamber need to be spaced away from each other in the installation thereof because of limited layout space in a vehicle, radiation noise due to the intake pulsation noise may be generated from a tube connecting between the compressor and the plenum chamber.
The present invention is directed to providing an air compressor that requires less installation space and allows reduction of noise development.